Sails



Oct. 1, 1968 H. BUSH 3,403,653

SAILS Filed Feb. 15, 1967 2 Sheets-Sheet l INVENTOR.

HAROLD BUSH Oct. 1, 1968 H. BUSH 3,403,653

SAILS riled Feb. 15, 1967 2 Sheets-Sheet 2 INVENTOR.

HAROLD BUSH 7y M y 74%; W

United States Patent Oflice 3,403,653 Patented Oct. 1, 1968 3,403,653SAILS Harold Bush, 9750 Knolson, Livonia, Mich. 48150 Filed Feb. 15,1967, Ser. No. 616,327 6 Claims. (Cl. 114-103) ABSTRACT OF THEDISCLOSURE A sail assembly formed of a series of elongated, rigid, panelsections arranged one above the other and each supported for rotationabout a horizontal axis. Each panel has an arcuate, longitudinal profiledefining a concave and convex side. Suitable lines provide means forrotating the panel sections simultaneously about their axis to controlthe propulsive force produced by the panels and the available windforce. A series of smaller panels are linked to the luff edge of eachpanel and selectively spaced from the convex sides thereof to define anozzle assembly. The nozzle assembly is arranged to deflect air from thewindward concave side of the panels to provide air streams forincreasing the negative pressure on the convex side of the panels.

Background of the invention This invention relates to watercraft andmore particularly to a sail assembly for watercraft having a pluralityof elongated overlapping panel sections supported for rotation andhaving means for moving the panel section in synchronization to controlthe magnitude of the propulsive force developed by the sail assembly anda wind force.

Description of the prior art Sails have long been used as a means forconverting a wind force to a directed thrust for a vessel.Conventionally sails utilize a fabric sheet which has two surfaces, oneof which is convex and the other corrrespondingly concave. This shape isnormally assumed when the sail is inflated by a wind force. The thrusteffect results from a directed circulation of the wind force acting onthe aerodynamic profile assumed by the sail so that a positive pressurearea is produced on the concave side of the sail and a lesser ornegative pressure area is prO- duced on the convex side of the sail. Thenet force developed by the positive and negative pressure areas producesa thrust on the mast in a direction determined by the plans of the sail.

Obviously the net force developed by the sail is a function of the areaof the sail. Thus a larger sail area will develop a larger directedforce on the vessel and a smaller sail area will produce a smallerforce. Thus, it can be seen that by varying the area of the sailpresented to the wind, that the resultant thrust produced on the vesselcan be varied to accommodate a desired rate of travel.

One attempt of the prior art to control the effect of the wind acting onthe sail by varying the area of the sail, other than by raising orlowering the sail, was disclosed in Patent No. 1,516,063 issued to F. A.Scammell Nov. 18, 1924. The Scammell patent disclosed a sail comprisinga series of canvas strips secured at their opposite ends to a boom andthe mast by means capable of adjustment. By tightening one edge of eachstrip and loosening the other edge, the wind effect could be controlledto a limited degree. The present application discloses a novelimprovement over the aforementioned art to produce a sail assemblyproviding a precise control for effectively employing the wind forceavailable to the sail.

Summary The preferred embodiment of the present invention, which will besubsequently described in detail, employs a series of rigid elongatedpanel sections arranged in overlapping relationship one above the other.Each panel section is supported for rotation about a horizontal axis andpreferably has a length extending from the luff to the leach of the sailassembly. The panels are rotatable about their individual axes for asynchronized movement between one extreme position wherein theycollectively present a continuous surface to the wind and a secondextreme position wherein they are arranged in spaced parallelrelationship. By rotating the panel sections about their respective axisto a selected angle, the horizontal thrust produced on the vessel can beprecisely cont-rolled and a vertical lift component developed.

Each panel section has an arcuate longitudinal cross section taking theform of an aerodynamic profile. The panels are formed of a rigidmaterial so that an optimum profile is available andpresented to thewind irrespective of fluctuations in wind forces. This Venetian Blindarrangement permits a more useful employment of the 'wind forceavailable while underway, and also permits a more eflicient maneuveringof the vessel while approaching a buoy or pier.

Each panel section is provided with a guide member at its luff edgewhich is slidably seated in a vertical slot provided in the mast topermit the sail assembly to be easily hoisted up the mast or collapsedtoward the boom.

It is well known that by increasing the velocity of the air streamflowing on the convex side of the sail assembly, that a greater negativepressure area can be achieved thereby producing a greater thrust from agiven wind force. The preferred embodiment of the present inventionprovides an efficient nozzle means for deflecting a quantity of air fromthe windward side of the sail assembly and directing this air in astream to the convex or downward side of the sail assembly. This nozzlemeans comprises a second series of smaller panel sections each of whichis associated with the luff edge of the main panels on their concaveside. Each nozzle panel is attached to its associated main panel by alink-age arranged to move the nozzle panel between a retracted positionwhere it is adjacent to the main panel and an extended position whereinit is spaced from its main panel to define a throat for receiving anddirecting a wind stream toward the convex side of the main panelassembly. A suitable linkage provides means for moving the nozzle panelsbetween their retracted and extended positions to a selected spacingfrom the main panel members.

It is therefore an object of the present invention to provide a sailassembly having contour retaining properties under varied windconditions by providing a series of elongated panels each having acontoured longitudinal cross section and arranged in overlappingrelationship to provide a continuous surface, each panel formed of arigid shape-retaining material.

It is another object of the present invention to provide a sail assemblyhaving means for readily reducing the effective sail area presented tothe wind without lowering or raising the sail by providing a series ofsail panels supported for synchronized rotation one above the otherabout horizontal axes and which are movable between a first extremeposition wherein they present a continuous surface to the wind and anopposite extreme position wherein they present spaced edgewise surfacesto the wind.

Still another object of the present invention is to provide an improvedsail assembly which may be easily hoisted and readily collapsed byproviding a series of panel sections each supported along a horizontalaxis and having a slide element along their luif edge which rides in avertical track formed in the mast.

Still further objects and advantages of the present invention willreadily occur to one skilled in the art to which the invention pertainsupon reference to the following detailed description.

Description of the drawings The description refers to the accompanyingdrawing in which like reference characters refer to like partsthroughout the several views and in which:

FIG. 1 is a perspective view depicting a sailing vessel propelled by asail assembly illustrating a preferred embodiment of the invention;

FIG. 2 is an enlarged view of the sail assembly illustrated in FIG. 1and with the panel sections rotated to present a full surface to thewind;

FIG. 3 is a fragmentary perspective view of the sail assemblyillustrated in FIG. 1 with the panel sections rotated to present aminimum surface to the wind;

FIG. 4 is an enlarged, exploded view of a typical panel assembly;

FIG. 5 is a view looking toward the leading edge of a typical panel;

FIG. 6 is a view of the panel assembly illustrated in FIG. 4 with thevarious elements assembled;

FIG. 7 is a view illustrating a nozzle panel spaced from the luff edgeof its panel to define a nozzle throat for directing air toward theconvex side of the panel.

Description of the invention Now referring to the drawings, FIG. 1illustrates a sailing vessel 10 having an upwardly directed mast 12 anda laterally directed boom 14 supporting a sail assembly 16.

Referring to FIGS. 2 and 3, the sail assembly 16 comprises a series ofelongated panels 18, each of which is supported for rotation about agenerally horizontal axis. The panels 18 are collectively rotatableabout their respective axes between a generally vertical positionwherein they cooperate to form a continuous surface as illustrated inFIG. 2 and an opposite extreme position wherein they each essentiallylie in spaced parallel relationship to one another as seen in FIG. 3.Each of the panels 18 is supported at its leading edge by a forwardlinkage mechanism 20 (FIG. 4) and at its trailing edge by a rearwardlinkage mechanism 22. The forward linkage mechanism provides aconnection between the luff edge of the panel and the mast 12 and therear linkage 22 provides a supporting connection between the leech ofeach panel and a cable 25. As can best be seen in FIG. 2 the cable 25extends from the tip of the mast 12 to the outer end of the boom 14.

The panels 18 are elongated about their horizontal axes and graduallyincrease in length from the uppermost panel to the lowermost panel toform a triangular configuration similar to what is known as a Marconirig.

A nozzle assembly 24 (FIG. 2) comprising a series of individual nozzlepanels 26 is associated with the luff of the sail assembly 16. Thenozzle assembly 24 is arranged so that the individual panels 26 may becollectively extended forwardly and away from the associated panels 18or retracted to a position adjacent the panels 18.

The nozzle assembly 24 is associated with the convex side of the sailassembly 16 and is intended to deflect air from the windward side of thesail assembly to create air stress on the convex side of the sailassembly thereby increasing the negative pressure on the downward sideto produce a greater net thrust from a given quantity of wind.

Now referring to FIGS. 4 and 6, a typical panel 18 is illustrated ashaving an arcuate longitudinal cross section and is preferably formed ofa rigid material so that an optimum cross section is always availableunder varying wind conditions. It will be noted that the arcuate crosssection provides a convex side 28 and a concave side 30.

4 A maximum horizontal thrust is developed by presenting the concavesides 30 to the wind.

The forward linkage 20 provides a connection with the leading edge ofthe panels 18 and the mast 12 and includes a generally T-shaped slidemember 32 slidably disposed in a vertical slot 34 defined in mast 12.Thus, the slide 32 is arranged so that the panels 18 may be raised to aselected height when getting underway, and lowered when the sailassembly is collapsed. Each slide 32 has a journal 33 for supporting asleeve 36 having a pair of laterally directed arms 38. A forwardsupporting arm 40 provides a rigid connection between the sleeves 36 andthe leading edge of the panel 18.

The trailing edge of each panel 18 is supported by an anchor member 42which is fixed to the cable 25. The anchor member 42 supports a shortshaft 44 on a rearward extension of the axis of the journal 33supporting the forward sleeve 36.

A rear supporting sleeve 46 is rotatably journaled on the shaft 44. Arear supporting arm 48 provides a rigid connection between the leech ofthe panel 18 and the sleeve 36. Each of the panels 18 has a similarlongitudinal profile so that when arranged in their overlappingposition, they form a continuous surface. The trailing edge of eachpanel 18 is progressively shortened from the lowermost panel to theuppermost panel. Thus, the rear supporting arm 48 of each panel isprogressively lengthened from the lowermost panel to the uppermostpanel. This structure is best illustrated in FIGURE 3.

Thus, it can be seen that each panel 18 is supported for rotation abouta generally horizontal axis defined by the journals 33 and the shafts44. To rotate the panels 18 to a selected angle, a pair of controlcables 50 and 52 are joined to the outer ends of arms 38- so that thepanels 18 can be simultaneously rotated to a selected position.

The nozzle panels 26 are each supported by a link 50 through a ball andsocket joint 52 to an actuating link 54. The link 54 is supported by asecond ball and socket joint 56 to a link 58 rigidly attached to thesupport 40. A third ball and socket joint 60 provides a connectionbetween an actuating lever 62 which is carried by a supporting crank 64.The supporting crank 64 is fixed against rotation to the journal 33. Theouter end of the support 62 is connected to an actuating cable 65. Thus,it can be seen that as the cable 65 is moved between lowered and raisedpositions, the nozzle panels 26 are collectively moved between aretracted position wherein they are disposed adjacent the main panels 18and an extended position wherein they are spaced from the leading edgeof their associated panels 18. Preferably the nozzle panels 26 arearranged so that they are in their extended position when the mainpanels 18 are in their overlapping vertical arrangement and in theirretracted position when the main panels 18 are in the raised parallelposition as illustrated in FIG. 3.

To provide stability to the panels 18 as they are simultaneously rotatedbetween their various positions, a cable 66 is wrapped around the rearsupporting sleeves 46 and rotates with the sleeves 46 as illustrated.

Although I have described but one preferred embodiment of my invention,it is to be understood that various changes and revisions can be madetherein without departing from the spirit of the invention as expressedby the scope of the appended claims.

I claim:

1. A sail asselrnbly useful in converting a wind force into a directedthrust for a vessel, comprising a series of generally horizontal panelsections, each of said panel sections being formed of a substantiallyrigid material and having an arcuate, longitudinal cross-sectiondefining concave and convex sides; and means supporting said panelsections along their lateral sides, one above the other.

2. A sail assembly as defined in claim 1, wherein each of said panelsare arranged one above the other in an overlapping relationship.

3. A sail assembly as defined in claim 1, wherein each of said panels issupported for rotation about a generally horizontal axis, and including*means for simultaneously rotating said panels about their individualhorizontal axes.

4. A sail assembly as defined in claim 3, wherein said panels arearranged in parallel relationship to one another throughout their arcsof rotation.

5. A sail assembly as defined in claim 4, including a series of nozzlepanels, said series of nozzle panels associated with the leading convexedges of said panels, said series of nozzle panels forming air nozzlemeans to deflect air from the concave side of said panel sections toproduce air streams on the convex side of said panels effective toincrease the area of negative pressure on the convex side of said panelsections.

6. A sail assembly as defined in claim 5, including link meansconnecting said nozzle panels to the leading edge of said panel sectionsfor movement between a first position wherein said nozzle panels areadjacent said panel sections and a second position wherein said nozzlepanels are spaced from said panel sections to define a nozzle means.

References Cited UNITED STATES PATENTS 1,504,057 8/ 192-4 Koelkebeck114-103 FOREIGN PATENTS 459,293 1/ 1937 Great Britain.

MILTON BUCHLER, Primary Examiner.

TRYGVE M. BLIX, Assistant Examiner.

